Revert engine (#31135)

* Revert "Support opacity layers for platform-views using hybrid-composition" (#31002)

* Revert "Support opacity layers for platform-views using hybrid-composition (#30264)"

This reverts commit 730b469.

* Empty

* Revert "[fuchsia] Switch from core-jit to core snapshots. (#30744)" (#31065)

This reverts commit a193f08.

Co-authored-by: Zachary Anderson <zanderso@users.noreply.github.com>
Co-authored-by: David Worsham <dworsham@google.com>

Author: 3 people